Method, system, and program for archiving files

ABSTRACT

Provided are a method, system, and program for archiving files. A hierarchical file system having directories is provided. An archival retention policy is associated with at least one of the directories in the hierarchical file system, wherein the retention policy applies to files included in the associated directory, and wherein the retention policy specifies a retention time indicating a time period during which a file is subject to the retention policy.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is related to a method, system, and program forarchiving files.

2. Description of the Related Art

Organizations may need to retain and archive electronic files (where afile comprises a document, record, or any other data structure storingcode or data that may be represented in a hierarchical file system) instorage for an extended period of time due to internal corporaterequirements or external regulatory or legal requirements. For instance,government regulators may require that certain files remain archived fora minimum period of time. Companies in regulated industries, such assecurities and financial organizations, defense contractors, etc., maybe required to archive certain documents. Further, government agenciesmay also be required to archive files. Yet further, organizationssubject to a government proceeding, such as litigation, may also besubject to a file retention policy. An organization may also archivedocuments for backup and storage, and versioning. A storage system oftenincludes some archival software to manage the archival of files atdifferent locations that are retained according to a policy. Sucharchival software may maintain a database of archived files. Use of thearchival software may require significant user training and management,as well as a stand alone application program. Archival softwaretypically features customized graphical user interfaces (GUIs) andapplication program interfaces (APIs) to interface with the operatingsystem to perform archival related operations.

One archival data storage technology referred to as WORM (for writeonce, read many) involves archiving data to a storage media, such asoptical disks, that can only be written to once. One disadvantage ofusing optical disks is that their access rates are slow, especially whenthe disks are maintained in an auto-changer that needs to mechanicallyaccess a disk from a slot and insert the accessed disk into a disk driveto access.

To avoid some of the drawbacks of using optical disks, some archivalsystem vendors are using inexpensive hard disk drives as the medium forarchiving data. The hard disk drive storage system is sold bundled withsoftware to expose the storage as a proprietary archive utility,requiring custom interfaces and application program interfaces to usethe archival features.

SUMMARY OF THE PREFERRED EMBODIMENTS

Provided are a method, system, and program for archiving files. Ahierarchical file system having directories is provided. An archivalretention policy is associated with at least one of the directories inthe hierarchical file system, wherein the retention policy applies tofiles included in the associated directory, and wherein the retentionpolicy specifies a retention time indicating a time period during whicha file is subject to the retention policy.

In further implementations, associating the archival retention policywith one directory comprises indicating a retention policy code in apathname of the directory.

In further implementations, a request directed to a target file isreceived and a determination is made as to whether the target file isincluded within the directory associated with the retention policy. Adetermination is made as to whether the retention time of the retentionpolicy indicates that the target file is currently subject to retentionin response to determining that the target file is included within thedirectory associated with the retention policy. The retention policy isapplied to the target file if the target file is currently subject tothe retention policy.

Yet further, the retention policy may comprise a non-re-writable andnon-erasable retention policy and wherein the directories and filestherein are stored in a magnetic storage medium.

Still further, additional subdirectories may be included in thedirectory associated with the retention policy such that the retentionpolicy applies to any file within the additional subdirectories.

Yet further, the directory associated with the retention policy is asubdirectory of another directory.

BRIEF DESCRIPTION OF THE DRAWINGS

Referring now to the drawings in which like reference numbers representcorresponding parts throughout:

FIG. 1 illustrates a computing environment in which embodiments of theinvention are implemented;

FIG. 2 illustrates an example of an arrangement of a hierarchical filesystem in accordance with implementations of the invention;

FIGS. 3, 4, and 5 illustrate operations performed to manage archivedfiles in accordance with implementations of the invention;

FIG. 6 illustrates a computing architecture that may be used toimplement the computing environment described with respect to FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following description, reference is made to the accompanyingdrawings which form a part hereof and which illustrate severalembodiments of the present invention. It is understood that otherembodiments may be utilized and structural and operational changes maybe made without departing from the scope of the present invention.

FIG. 1 illustrates a computing environment in which embodiments of theinvention are implemented. A host system 2 includes an operating system4 and a file system 6 that provides an organization of files stored in astorage device. The file system 6 may implement a hierarchical tree-likearrangement of files, which may involve the use of directories andsubdirectories in which the files or records may be stored, where anydirectory may comprise a subdirectory of another directory or the rootdirectory. A file system user interface 8 provides a command line orgraphical user interface to enable the user to explore the file systemand perform file system related operations, such as moving a file to aspecified directory, deleting a file, renaming a file, creating a file,etc. The file system user interface 8 may comprise a file managementprogram that renders a presentation of the hierarchical arrangement offiles. The file system user interface 8 may comprise a stand-alone filemanagement program or a file management function accessed through anapplication program.

An archival filter 10 intercepts user file requests generated throughthe file system user interface 8 directed to the file system 6 anddetermines whether any archival retention policies should block suchuser requested operation if necessary or allow the operation to proceedto the file system 6 to execute. The file system 6 may provide access tofiles stored in the storage system 12 via connection 14.

The host system 2 may comprise any computing device known in the art,such as a server class machine, workstation, desktop computer, etc. Thestorage system 12 may comprise any storage device known in the art, suchone or more interconnected disk drives configured as a Redundant Arrayof Independent Disks (RAID), Just a Bunch of Disks (JBOD), Direct AccessStorage Device (DASD), as a tape storage device, a single or multiplestorage units, e.g., a tape library, or etc. The connection 14 maycomprise any interface between storage and a host known in the art, suchas a network connection (e.g., Ethernet, wireless ethernet, FibreChannel, etc.) or any other data transfer interface known in the art,e.g., Advanced Technology Attachment (ATA), Serial ATA (SATA), SmallComputer System Interface (SCSI), etc., which may be external orinternal to the host 2 enclosure.

In certain embodiments, the archival filter 10 determines the retentionpolicies based on a pathname of a directory associated with a retentionpolicy. For instance, to indicate that files or records within adirectory are to be retained for a specified time period, the user mayname a directory “/RetainX”, where X specifies a time period, e.g.,years, days, months, etc. In certain implementations, the action of“retaining” a file may entail never allowing the file to be modified orupdated in any circumstances, and only permitting erase and moveoperations. The retention policy indicated in the pathname of thedirectory would apply to any files or records stored within thedirectory having the retention pathname or any further subdirectory ofthe directory having the retention name. FIG. 2 illustrates ahierarchical tree file system in which data is organized having twodirectories 30 and 32. The archival policy specified in the pathnames ofthe retention directories 30 and 32 may apply to files stored in theretention directories 30 and 32 or any subdirectories defined therein.The user may use the file system user interface 8 to move files to aretention directory, such as by using an input device to “drag and drop”or otherwise move files from one directory to a retention directory 30and/or 32 so that the retention policy will apply to the moved file.

Another example of a retention policy to use as the pathname is“RetainUntilX”, which specifies that files in a retention directoryhaving such a pathname will be retained until the specified date “X”.

In this way, the user may use standard file management interfaces toassociate a file with a retention policy by just copying or otherwisemoving the desired file to a retention directory. With the describedembodiments, specialized APIs or customized interfaces are not neededbecause a standard file management interface is used to specify theretention policies. Moreover, the user can define a retention policy byincluding descriptive language statements in the directory pathname,which are understood by the archival filter 10, that describe andspecify the policy. This avoids the need for substantial training toinstruct users on how to apply an archival policy to a file.

FIG. 2 illustrates an example of a hierarchical arrangement ofdirectories, where the pathnames of the directories 30 and 32 provide afile retention policy to apply to all files in that directory. Forinstance any file within the directory 30 or a subdirectory of directory30 will be retained for three years. When the date and time associatedwith a file, i.e., the last modification date, within the directory 30is three years prior to the current date, then that file in thedirectory 30 may be deleted or moved without restriction. Similarly, anyfile in the path of a subdirectory of directory 32 will be retained forfive years.

FIG. 2 also provides an example of a “hold” directory 34, which is asubdirectory of the retain directory 36 and litigation proceedingssubdirectory 36. Any file moved to the hold directory 34 will not beallowed to be deleted, even after the expiration of the retention periodindicated in the pathname of the directory 32. For instance, if certainfiles may be relevant to an imminent or pending litigation, then a holddirectory 34 may be added as a subdirectory of the directory 36 to storefiles relevant to the litigation to prevent any files moved to the holddirectory 34 from being deleted. A regulatory filings directory 38archives files related to regulatory filings. In certain embodiments, afile in the hold directory 34 may be moved back to the directory fromwhich it originated or another directory after the reason for the holdis no longer relevant.

FIG. 3 illustrates operations performed by the archival filter 10 todetermine whether an archive policy applies to an operation to modify afile represented in the file system 6. The archival filter 10 wouldintercept and process a modify request before the request is sent to thefile system 6 to execute. Upon receiving (at block 100) the request tomodify the target file, if (at block 102) the target file to modify isnot within a retention directory (directly or within a furthersubdirectory thereof), then the archival filter 10 passes (at block 104)the modify request to the file system 6 to execute. If the target fileis within a retention directory, then the archival filter 10 returns (atblock 106) a message indicating denial of the erase request due to aretention policy. The message may include additional information such asthe specifics of the retention policy and the pathname of the directoryincluding the target file.

With the logic of FIG. 3, any request to modify a file, as opposed toerase the file, may be denied regardless of whether the archival policyapplies. This bar on modifying archived files regardless of theretention policy would prevent the situation from occurring where a filewhose retention period expired is modified and subsequently subjected toa new archival retention policy. If such modification were allowed, thenthe new archival policy may be applied when the assumption is that thefile subjected to the new archival policy was the previously archivedfile, not an updated version thereof.

FIG. 4 illustrates operations performed by the archival filter 10 todetermine whether an archive policy applies to an operation to erase afile represented in the file system 6. The archival filter 10 wouldintercept and process an erase request before the request is sent to thefile system 6 to execute. Upon receiving (at block 120) the request toerase the target file, if (at block 122) the target file to erase is notwithin a retention directory (directly or within a further subdirectorythereof), then the archival filter 10 passes (at block 124) the eraserequest to the file system 6 to execute. If the target file is within aretention directory, then a determination is made (at block 126) as towhether the retention policy specified in the pathname of the directoryindicates an expirable retention period. A retention policy that doesnot expire may be indicated in the directory pathname with “hold”,retain forever, etc. If (at block 126) the retention policy does notexpire, then the archival filter 10 returns (at block 128) a messageindicating denial of the erase request due to a retention policy. Themessage may include additional information such as the specifics of theretention policy and the pathname of the directory including the targetfile. If (at block 126) the retention policy is for a defined, i.e.,expirable, time period and if (at block 130) the retention period hasexpired, then control proceeds to block 124 to allow the erase requestto proceed. Otherwise, if the retention period has not expired, thencontrol proceeds to block 108 to return the message denying the eraserequest.

A retention period expires if the time period of the retention policyhas been exceeded. For instance, if the retention period specifies atermination date, e.g., “RetainUntil_(—)1/1/05”, then the retentionperiod expires on the specific date. Alternatively, if the retentiontime period specifies a time frame, e.g., “Retain_(—)3Years”, then theretention period expires when the current time exceeds the retentiontime period plus the time the file was created, last modified or addedto the retention directory.

With the logic of FIG. 4, an erase operation is not allowed to proceedif a file is within a retention directory and the retention policy hasnot expired with respect to that target file. Thus, files with differentcreation/last modification dates may expire at different times accordingto certain retention policies specified in the directory file name. Inthis way, the archival filter 10 filters all erase requests. In certainimplementations, the archival filter 10 would pass all read requests tothe file system 6 to execute.

FIG. 5 illustrates operations performed by the archival filter 10 toprocess a request to move a target file from one directory to another.Upon receiving (at block 150) the request to move the target file, if(at block 152) the file is not within a directory whose file namespecifies a retention policy, then the archival filter 10 passes (atblock 154) the move request to the file system 6 to execute. If (atblock 152) the target file is within a directory associated with aretention policy and if (at block 156) the retention policy does notspecify an expirable retention time period, e.g., such as the case withthe hold directory 34, then a determination is made (at block 158)whether the move is to a permitted directory. In certainimplementations, a permitted target directory may be one whose files areassociated with a retention policy that is as long or longer than theretention policy associated with the directory including the holddirectory. For instance, in the example of FIG. 2, a file moved from thehold directory 34 would have to be moved to a directory having aretention policy of at least five years. In alternative implementations,a permitted directory may be associated with shorter retention timeperiods or no retention policies. If (at block 158) the move is to apermitted directory, then control proceeds to block 154 to pass the movecommand to the file system 6 to execute; otherwise, if the move is notto a permitted directory, then the archival filter 10 causes the return(at block 160) of a message indicating denial of the move due to aretention policy.

If (at block 156) the retention policy does provide an expirable(finite) time period and if (at block 162) the retention time period hasexpired, e.g., the specified termination date has passed or atermination period from the file date has expired, then control proceedsto block 154 to pass the move request to the file system 6 to execute.Otherwise, if the retention time period has not expired and if (at block166) the target directory of the move has a same or longer retentionpolicy than the retention policy of the directory currently includingthe target file, then control proceeds to block 154 to allow the filesystem 6 to execute the move request. If (at block 166) the targetdirectory has a shorter retention time period than the current directoryincluding the target file, then control proceeds to block 160 to denythe move request.

With the logic of FIG. 5, a file can be moved from a directoryassociated with a finite retention policy, i.e., one with an expirabletime period, if the file is being moved to a directory having at leastas long or longer than retention period. For instance, if a file is in adirectory having a retain forever retention period, like the holddirectory 34 (FIG. 2), then a file in that hold directory may only bemoved to another hold directory also having the retain forever retentionperiod. Further, if the file being moved is in a higher level directory,which contains the hold directory, then the file can only be moved to ahold directory within a higher level directory having the same or longerretention period of the higher level directory including the filesubject to the move. This ensures that the file initially associatedwith the retention policy is retained for the specified period evenafter being moved. In further implementations, there may be a specialdirectory for archived files removed from a retention directory to allowtracking of any files removed from the retention archives.

Certain of the described implementations provide techniques for using astandard file system interface to allow the user to implement anon-re-writable and non-erasable archival system, thereby avoiding theneed to install, train for, and use a separate stand alone applicationprogram. With certain of the described implementations, the userspecifies retention policies by associating retention policies withdirectories of the file system including the archived files to implementa non-re-writable and non-erasable environment.

Additional Implementation Details

The archival file management system described herein may be implementedas a method, apparatus or article of manufacture using standardprogramming and/or engineering techniques to produce software, firmware,hardware, or any combination thereof. The term “article of manufacture”as used herein refers to code or logic implemented in hardware logic(e.g., an integrated circuit chip, Programmable Gate Array (PGA),Application Specific Integrated Circuit (ASIC), etc.) or a computerreadable medium, such as magnetic storage medium (e.g., hard diskdrives, floppy disks, tape, etc.), optical storage (CD-ROMs, opticaldisks, etc.), volatile and non-volatile memory devices (e.g., EEPROMs,ROMs, PROMs, RAMs, DRAMs, SRAMs, firmware, programmable logic, etc.).Code in the computer readable medium is accessed and executed by aprocessor. The code in which preferred embodiments are implemented mayfurther be accessible through a transmission media or from a file serverover a network. In such cases, the article of manufacture in which thecode is implemented may comprise a transmission media, such as a networktransmission line, wireless transmission media, signals propagatingthrough space, radio waves, infrared signals, etc. Thus, the “article ofmanufacture” may comprise the medium in which the code is embodied.Additionally, the “article of manufacture” may comprise a combination ofhardware and software components in which the code is embodied,processed, and executed. Of course, those skilled in the art willrecognize that many modifications may be made to this configurationwithout departing from the scope of the present invention, and that thearticle of manufacture may comprise any information bearing medium knownin the art.

In certain described implementations, the user associates a retentionpolicy with a directory by indicating a retention policy code in thename of the directory to apply to all files included in that directory.In alternative implementations, the user may associate a retentionpolicy with a directory in a manner other than coding the pathname ofthe directory. For instance, the user may associate retention policieswith the attributes defined for a directory of the file system, whichmay or may not be indicated in the name of the directory or graphicalrendering of the directory in a graphical user interface providing arendering of the hierarchical file system. In certain operating systems,such as the MICROSOFT WINDOWS operating system, the attributes that maybe assigned to a directory are accessed by right clicking a mouse buttonover the name of the directory displayed in a user interface window todisplay a menu, and then selecting the properties option displayed inthe menu. (Microsoft and Windows are registered trademarks of MicrosoftCorporation).

In certain described implementations, the archival filter 10 is shown asa separate program component. The archival filter 10 may be installedseparately from the file system 6, such as a separately installedapplication program that runs when the operating system 4 and filesystem 6 are initialized and screens files the user is attempting toerase or move. Alternatively, the functionality of the archival filtermay be incorporated directly in the operating system and be madeavailable as a feature of the file system installed with the operatingsystem. The archival filter 10 may execute in the kernel of theoperating system or at different priority levels.

In described implementations, a retention policy associated with adirectory applied to all files within that directory, including files insubdirectories of the directory associated with the retention policy. Infurther implementations, certain subdirectories within the retentionpolicy directory may include files not subject to the retention policy,such as the case with a hold directory grouping files that are retainedindefinitely, irrespective of any retention policy associated with adirectory in which the hold directory is included.

In described implementations, a non-re-writable and non-erasable typerestriction policy is applied to files in a directory associated withthe retention policy for the time period specified by the retentionpolicy. In alternative implementation, different retention restrictionsmay be applied to files subject to the retention policy.

In described implementations, the coding of the retention policy in thedirectory pathname comprised a description of the retention policy. Inalternative implementations, the coding of the retention policy in thepathname may comprise a code that is not descriptive of the retentionpolicy. For instance, the pathname may be coded with “Retain3Years”,which is a description of the retention policy, or a non-descriptivecode, e.g., “X11”, which may not provide any description of the actualretention policy.

FIGS. 3, 4, and 5 describe specific operations occurring in a particularorder. In alternative implementations, certain operations may beperformed in a different order, modified or removed. Morever, steps maybe added to the above described logic and still conform to the describedimplementations. Further, operations described herein may occursequentially or certain operations may be processed in parallel. Yetfurther, operations may be performed by a single processing unit or bydistributed processing units.

FIG. 6 illustrates one implementation of a computer architecture 200 ofthe host system 2 shown in FIG. 1. The architecture 200 may include aprocessor 202 (e.g., a microprocessor), a memory 204 (e.g., a volatilememory device), and storage 206 (e.g., a non-volatile storage, such asmagnetic disk drives, optical disk drives, a tape drive, etc.). Thestorage 206 may comprise an internal storage device or an attached ornetwork accessible storage. Programs in the storage 206 are loaded intothe memory 204 and executed by the processor 202 in a manner known inthe art. The architecture further includes a network card 208 to enablecommunication with a network. An input device 210 is used to provideuser input to the processor 202, and may include a keyboard, mouse,pen-stylus, microphone, touch sensitive display screen, or any otheractivation or input mechanism known in the art. An output device 212 iscapable of rendering information transmitted from the processor 202, orother component, such as a display monitor, printer, storage, etc.

The foregoing description of the implementations has been presented forthe purposes of illustration and description. It is not intended to beexhaustive or to limit the invention to the precise form disclosed. Manymodifications and variations are possible in light of the aboveteaching. It is intended that the scope of the invention be limited notby this detailed description, but rather by the claims appended hereto.The above specification, examples and data provide a completedescription of the manufacture and use of the composition of theinvention. Since many implementations of the invention can be madewithout departing from the spirit and scope of the invention, theinvention resides in the claims hereinafter appended.

1. A method for archiving files, comprising: providing a hierarchicalfile system having directories; and associating an archival retentionpolicy with at least one of the directories in the hierarchical filesystem, wherein the retention policy applies to files included in theassociated directory, and wherein the retention policy specifies aretention time indicating a time period during which a file is subjectto the retention policy.
 2. The method of claim 1, wherein associatingthe archival retention policy with one directory comprises indicating aretention policy code in a pathname of the directory.
 3. The method ofclaim 2, wherein the retention policy code in the pathname specifies atime period during which the retention policy applies to files withinthe directory.
 4. The method of claim 3, wherein the retention policycode in the pathname of the directory provides a description of theretention policy.
 5. The method of claim 1, wherein the time periodcomprises one of: a specified date, wherein the retention policy appliesto files in the directory prior to the specified date; a specified timeperiod, wherein the retention policy applies to each file in thedirectory for the specified time period following a time the file wasmodified; and an unlimited period of time.
 6. The method of claim 1,further comprising: receiving a request directed to a target file;determining whether the target file is included within the directoryassociated with the retention policy; determining whether the retentiontime of the retention policy indicates that the target file is currentlysubject to retention in response to determining that the target file isincluded within the directory associated with the retention policy; andapplying the retention policy to the target file if the target file iscurrently subject to the retention policy.
 7. The method of claim 6,wherein the retention policy applies up until the retention time, andwherein the retention policy applies to the target file if a currenttime is not greater than the retention time.
 8. The method of claim 6,wherein the retention time specifies a time period, and wherein theretention policy applies to the target file if a current time is notgreater than a time comprising a time the target file was last modifiedplus the specified time period.
 9. The method of claim 6, wherein therequest directed to the target file comprises a request to erase or movethe target file, and wherein applying the retention policy comprisespreventing the request to erase or move the target file from occurring.10. The method of claim 6, wherein if the target file is not currentlysubject to the retention policy, then allowing the received requestdirected to the target file to proceed.
 11. The method of claim 6,further comprising: determining whether the target file is includedwithin a directory associated with an unlimited retention that is asubdirectory of the directory associated with the retention policy,wherein the received request directed to the target file is not allowedto proceed if the target file is also included within one directoryassociated with the unlimited retention even if the target file is notcurrently subject to the retention policy.
 12. The method of claim 6,wherein the received request comprises a request to move the target filefrom a current directory including the target file to a targetdirectory, and wherein applying the retention policy further comprises:allowing the target file to be moved to the target directory if thetarget directory is associated with a retention policy that has a sameor longer retention time than the retention policy associated with thecurrent directory; and denying the requested move operation if theretention policy associated with the target directory has a shorterretention time than that for the retention policy associated with thecurrent directory.
 13. The method of claim 1, wherein the retentionpolicy comprises a non-re-writable and non-erasable retention policy andwherein the directories and files therein are stored in a magneticstorage medium.
 14. The method of claim 1, wherein additionalsubdirectories may be included in the directory associated with theretention policy, and wherein the retention policy applies to any filewithin the additional subdirectories.
 15. The method of claim 1, whereinthe directory associated with the retention policy is a subdirectory ofanother directory.
 16. A system for archiving files, comprising: amemory device including a hierarchical file system having directories;and means for associating an archival retention policy with at least oneof the directories in the hierarchical file system, wherein theretention policy applies to files included in the associated directory,and wherein the retention policy specifies a retention time indicating atime period during which a file is subject to the retention policy. 17.The system of claim 16, wherein the means for associating the archivalretention policy with one directory indicates a retention policy code ina pathname of the directory.
 18. The system of claim 16, wherein theretention policy code in the pathname specifies a time period duringwhich the retention policy applies to files within the directory. 19.The system of claim 16, wherein the time period comprises one of: aspecified date, wherein the retention policy applies to files in thedirectory prior to the specified date; a specified time period, whereinthe retention policy applies to each file in the directory for thespecified time period following a time the file was modified; and anunlimited period of time.
 20. The system of claim 16, furthercomprising: means for receiving a request directed to a target file;means for determining whether the target file is included within thedirectory associated with the retention policy; means for determiningwhether the retention time of the retention policy indicates that thetarget file is currently subject to retention in response to determiningthat the target file is included within the directory associated withthe retention policy; and means for applying the retention policy to thetarget file if the target file is currently subject to the retentionpolicy.
 21. The system of claim 20, wherein the retention policy appliesup until the retention time, and wherein the retention policy applies tothe target file if a current time is not greater than the retentiontime.
 22. The system of claim 20, wherein the retention time specifies atime period, and wherein the retention policy applies to the target fileif a current time is not greater than a time comprising a time thetarget file was last modified plus the specified time period.
 23. Thesystem of claim 20, wherein the request directed to the target filecomprises a request to erase or move the target file, and wherein themeans for applying the retention policy prevents the request to erase ormove the target file from occurring.
 24. The system of claim 20, whereinif the target file is not currently subject to the retention policy,then the received request directed to the target file is allowed toproceed.
 25. The system of claim 20, further comprising: means fordetermining whether the target file is included within a directoryassociated with an unlimited retention that is a subdirectory of thedirectory associated with the retention policy, wherein the receivedrequest directed to the target file is not allowed to proceed if thetarget file is also included within one directory associated with theunlimited retention even if the target file is not currently subject tothe retention policy.
 26. The system of claim 20, wherein the receivedrequest comprises a request to move the target file from a currentdirectory including the target file to a target directory, and whereinthe means for applying the retention policy further performs: allowingthe target file to be moved to the target directory if the targetdirectory is associated with a retention policy that has a same orlonger retention time than the retention policy associated with thecurrent directory; and denying the requested move operation if theretention policy associated with the target directory has a shorterretention time than that for the retention policy associated with thecurrent directory.
 27. The system of claim 16, wherein additionalsubdirectories may be included in the directory associated with theretention policy, and wherein the retention policy applies to any filewithin the additional subdirectories.
 28. The system of claim 16,wherein the directory associated with the retention policy is asubdirectory of another directory.
 29. An article of manufacture forarchiving files, wherein the article of manufacture causes operations tobe performed, the operations comprising: providing a hierarchical filesystem having directories; and associating an archival retention policywith at least one of the directories in the hierarchical file system,wherein the retention policy applies to files included in the associateddirectory, and wherein the retention policy specifies a retention timeindicating a time period during which a file is subject to the retentionpolicy.
 30. The article of manufacture of claim 29, wherein associatingthe archival retention policy with one directory comprises indicating aretention policy code in a pathname of the directory.
 31. The article ofmanufacture of claim 30, wherein the retention policy code in thepathname specifies a time period during which the retention policyapplies to files within the directory.
 32. The article of manufacture ofclaim 31, wherein the retention policy code in the pathname of thedirectory provides a description of the retention policy.
 33. Thearticle of manufacture of claim 29, wherein the time period comprisesone of: a specified date, wherein the retention policy applies to filesin the directory prior to the specified date; a specified time period,wherein the retention policy applies to each file in the directory forthe specified time period following a time the file was modified; and anunlimited period of time.
 34. The article of manufacture of claim 29,wherein the operations further comprise: receiving a request directed toa target file; determining whether the target file is included withinthe directory associated with the retention policy; determining whetherthe retention time of the retention policy indicates that the targetfile is currently subject to retention in response to determining thatthe target file is included within the directory associated with theretention policy; and applying the retention policy to the target fileif the target file is currently subject to the retention policy.
 35. Thearticle of manufacture of claim 34, wherein the retention policy appliesup until the retention time, and wherein the retention policy applies tothe target file if a current time is not greater than the retentiontime.
 36. The article of manufacture of claim 34, wherein the retentiontime specifies a time period, and wherein the retention policy appliesto the target file if a current time is not greater than a timecomprising a time the target file was last modified plus the specifiedtime period.
 37. The article of manufacture of claim 34, wherein therequest directed to the target file comprises a request to erase or movethe target file, and wherein applying the retention policy comprisespreventing the request to erase or move the target file from occurring.38. The article of manufacture of claim 34, wherein if the target fileis not currently subject to the retention policy, then allowing thereceived request directed to the target file to proceed.
 39. The articleof manufacture of claim 34, wherein the operations further comprise:determining whether the target file is included within a directoryassociated with an unlimited retention that is a subdirectory of thedirectory associated with the retention policy, wherein the receivedrequest directed to the target file is not allowed to proceed if thetarget file is also included within one directory associated with theunlimited retention even if the target file is not currently subject tothe retention policy.
 40. The article of manufacture of claim 34,wherein the received request comprises a request to move the target filefrom a current directory including the target file to a targetdirectory, and wherein applying the retention policy further comprises:allowing the target file to be moved to the target directory if thetarget directory is associated with a retention policy that has a sameor longer retention time than the retention policy associated with thecurrent directory; and denying the requested move operation if theretention policy associated with the target directory has a shorterretention time than that for the retention policy associated with thecurrent directory.
 41. The article of manufacture of claim 29, whereinthe retention policy comprises a non-re-writable and non-erasableretention policy and wherein the directories and files therein arestored in a magnetic storage medium.
 42. The article of manufacture ofclaim 29, wherein additional subdirectories may be included in thedirectory associated with the retention policy, and wherein theretention policy applies to any file within the additionalsubdirectories.
 43. The article of manufacture of claim 29, wherein thedirectory associated with the retention policy is a subdirectory ofanother directory.